yaxley



(No Model 2 Sheets-Sheet 2.

E. E. YAXLEY 8: J. H. RILEY.

TELEPHONE EXCHANGE SYSTEM.

1%. 547,388. Patented Oct. 1, 1895.

mac.

ERNEST E. YAXLEY AND JOHN H. RILEY, OF CHICAGO, ILLINOIS, ASSIGNORS OFONE-HALF TO LE ROY BROWN, OF SAME PLACE.

TELEPHONE-EXCHANGE SYSTEM.

SPECIFICATION forming part of Letters Patent No. 547,388, dated October1, 1895.

Application filed January 14, 1895. Serial No. 534,860- (No model.)

To all whom it may concern:

Be it known that we, ERNEST E. YAXLEY and JOHN H. RILEY, citizens of theUnited States, residing at Chicago, in the county of Cook and State ofIllinois, have invented a certain new and useful Improvement inTelephone-Exchange Systems; and we do hereby declare the following to bea full, clear, and exact description of the same, reference being had tothe accompanying drawings, forming a part of this specification.

The present invention relates to a system of circuits for telephonecommunication in connection with a central exchange'or station; and theobjects of the present improvement are to provide a simple and efficientsystem of telephone-circuits, either metallic or ground, in which thetelephone or talking circuit and the signal or calling circuit arearranged as substantially independent circuits, but preferably with acommon return, and in which improved construction a direct and metallictalking-circuit of a minimum resistance is provided, and whicharrangement has a further advantage in that it avoids in a very simpleand efficient manner the usual feature of a shunt circuit around thegenerator of the subscribers call or signal, in that in the presentsystem a generator of the required power in the central station isadapted to ring such subscribers signal through the armature winding ofsuch subscribers call-generator.

Other features of merit in the present sys tem are as follows: Thesubscribers telephone-switch, either opened or closed, does not affectthe sending of a call or signal. Again, the subscribers signals or callsdo not signal or call each other, but are rung from the central stationby a generator at that point; and, again, in sending a signal from thecentral station, the annunciator-coil, being out of circuit, will not beactuated to give an annunciation. By this means the labor of re settingthe annunciator-drop after such signal is saved. Ihe above objects areattained by a construction and arrangement of parts substantially asshown in the accompanying drawings, in which-=- Figure l is adiagrammatic view illustrating a pair of subscribers stations and theconnections thereof with the central station or exchange. Fig. 2 is asimilarview illustrat ing a modified arrangementfrom that shown in Fig.1; Fig. 3, a detail viewot' the flexiblyconnected plugs used in thecentral station.

Similar letters and numerals indicate like parts in the several Views.

In the accompanying drawings I have illustrated a pair of subscribers"or local telephone-stations connected by the individual wires orcircuits to the central or operatives station. Any desired number ofsuch. local or subscribersstations may be arranged in a similar manner,as the requirements may indicate.

Referring to the drawings, 0 represents the central station, and L and La series of two subscribers or local stations connected to the centralstation by their individual wires 1 1, 2 2, and 3 3, 4. 4'. Eachsubscribers or local station will be provided with the usual signal orcall 5 or 5, a transmitter 6 or 6', a receiver 7 or 7, and a switch 8 or8', controlling the local battery, and which may be either manual orautomatic in its operation. The central station 0 will be provided witha generator 9, a transmitter 10, a receiver 11, and a companion seriesof annunciators 1:2 12', sockets or bushings 13 13', and push buttons orswitches 1414c, equal in number and connected in an individual mannerwith the subscribers stations L L, as hereinafter set forth.

In the present improvement each individual signal or call circuit of alocal station L or L, in so far as it relates to sending a signal from asubscribers or local station to the central station, will be formed bythe wires 3 4 or 3' 4, as the case may be, and such circuit will embracethe local signal or call 5 or 5', the annunciator 12 or 12', the switch14: or 14. Current starting from a pole of the generator of the localsignal or call 5 or 5' passes through wire 3 or 3 to the switch-lever 15or 15 to upper contact point 16 or 16', and through wire 17 or 17' tothe annunciator 12 or 12 to give a visible signal in the centralstation, and from thence back through the wire 4 or 4 to the oppositepole of the gener' ator of the local signal or call 501? 5'. In likemanner the individual telephone or talking circuit of a local station Lor L, in so far as it relates to talking between two local stations,wil1be formed by the wires 1 2 or 1 2, extending to their respective socketsor bushings 13 13' at the central station. Now with these two bushings13 13 electrically coupled by the flexibly-connected plugs 18, starting,for example, from one pole of the secondary circuit of theinduction-coil of the transmitter 6, the current passes through thereciver 7 and line-Wire 1 to the bushing 13 and through the flexibleconductor-coupling 18 to the bushing 13, and from thence through theline-wire l to the receiver 7, the current returning from thence throughthe inductioncoil of the receiver 7 overline 2 to the generalconnecting-strip 19 in the central station 0, and from thencethrough,0ver line-wire 2, completing the circuit.

In the present improvement the central station or operatorssignal-circuit to each subscribers station will comprise the centralgenerator 9, connected by line 20 with the lower contact-points 21 21'of the switch 14 14' before described, such central generator having areturn-connection 22 to the general connecting-strip 19. With theswitch-lever 15 in contact with the lower contact-point 21 or 21, theindividual annunciator-coil 12 or 12 will be cut out of circuit, and thecurrent passes through line-wire 3 or 3 to the subscribers call orsignal 5 or 5 to sound an alarm, and returns through the line-wire 4 or4 down to the general connecting-strip 19, to which said lines 4 or 4are connected by a branch wire extending from the point of connectionthereof to annunciators 12 12 down to such general connecting-strip, thecurrent returning thence to the central generator 9 throughreturn-connection 22. The central station oroperatives telephone ortalking circuit to each subscribers station will comprise a secondarycentral station, connecting-strip 28, that is connected by wires 24 25with the operators transmitter 10, receiver 11, and the generalconnecting-strip 19, the opposite end of the secondary connecting-strip23 being provided with a flexibly-connected contactpoint 26, for apurpose hereinafter set forth.

In connecting up the central station with any particular subscribersstation, the individual bushing 13 or 13' thereof is connected to thesecondary connecting-strip 23, either by the ordinary flexibly-connectedcontact-point 18 or by the flexibly-connected contact-point 26. Withthis connection the central-station talking-circuit formed by the wires24: and 25 is in communication with the subscribers talking circuit,heretofore described, and where two subscribers talking-circuits areconnected together the central-station talkingcircuit will be connectedthereto in multiple, so that the central station operative cancommunicate with either of such subscribers. For example, in talkingfrom the central station to subscribers station L, the current passingfrom the central transmitter over the line 24, secondaryconnecting-strip 23, flexibly-connected coupling 18 or 26, bushing 13,line 1,

and subscribers receiver 7; returning through the induction-coil of thetransmitter 6, line 2, general connecting-strip 19, line 25, andreceiver 11, back to the transmitter 10.

In ordinary use the flexibly-connected contact-points 18 will be themost convenient and ready means for making connections between any ofthe individual bushings 13 13' and the secondary connecting-strip 23,and it is only when such flexibly-connected contact-points are in use asa connecting-coupling between a pair of such bushings that theflexibly-connected contact-point 26 need be used to cut in thecentral-station talking-circuit.

In the modified arrangement of the present system, as illustrated inFig. 2, the main and essential difference from that shown in Fig. 1consists in employing a ground or common return for lines t and 4c, thegeneral connecting-strip 19 being also grounded or con nected to thecommon return-wire.

Having thus fully described our said invention, what we claim as new,and desire to secure by Letters Patent, is

1. In a telephone exchange system, the combination of the series ofseparate and entirely independent talking and call circuits for thesubscribers stations, separate and independent talking and call circuitsin the central station, aseries of annunciators, switches, and bushingsin the central station, that have connection with the subscriberscircuits, a general connecting strip, at the central station, havingconnection with the central station circuits, and with the returns ofthe sub scribers circuits, and a connection extending from the centralstation, talking circuit, and adapted to make connection with any of theseries of subscribers bushings, the talking and call circuits of thesubscribers stations, being capable of simultaneous and independent use,substantially as set forth.

2. In a telephone exchange system, the combination of the series ofseparate and entirely independent talking and call circuits for thesubscribers stations, separate and independent talking and call circuitsin the central station, a series of annunciators, switches, and bushingsin the central station, that have connection with the subscriberscircuits, a general connecting strip, at the central station, havingconnection with the central sta tion circuits, and with the returns ofthe subscribers circuits, a secondary connecting strip connected to thecentral station, talking circuit, and means for connecting the same,with any of the series of subscribers bushings, the talking and callcircuits of the subscribers stations, being capable of simultaneous andindependent use,substantially as set forth.

3. In a telephone exchange system, the combination of the series ofseparate and entirely independent talking and call circuits for thesubscribers stations, separate and independent talking and call circuitsin the central statioma series of annunciators, switches and bushings,in the central station, that have connection with the subscriberscircuits, a general connecting strip at the central station, havingconnection with the central station circuit, and with the returns of thesubscribers circuits, a secondary connecting strip connected to thecentral station talking circuit, and means for connecting the same, withany of the series of subscribers bushings, such means consisting of aflexibly connected contact point 26, the talking and call circuits ofthe subscribers stations, being capable of simultaneous and independentuse, substantially as set forth.

In testimony whereof witness our hands I 5 this 11th day of January,1895.

ERNEST E. YAXLEY; JOHN H. RILEY.

In presence of-- ROBERT BURNS, GEO. H. ARTHUR.

